Telephone-exchange system



A. F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7, I917.

Patented May 25,1920.

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TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7. 1917.

Patented May25,1920.

8 SHEETSSHEET 2.

12,31 ,62 I446 WM A. F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7. 917.

Patented May 25, 1920.

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A. F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7. 1917.

1,340,940, Patented May 25, 1920.

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A..F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

A. F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7. 1917.

Patented May 25, 1920.

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A. F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7, I9I7.

Patented May 25, 1920.

I I I I I I I Q @R i 8 SHEETS-SHEET 7- A. F. DIXON AND F. N. REEVES.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 7. 1911.

7'0 oPER TELJSEZ //7 V6/7/0/6. /4/7705 f. O/xon. Frank A/ fiee V6.5. y

Patented May 25, 1920.

UNITED STATES PATENT OFFICE.

AMOS E. DIXON AND 'F. .ANK n. REEvEs, 0E NEwARK, NEW JERSEY, nssmim To wEsTERN ELEoTRIo omrANY, mcoR'roRATEn, on NEW YORK, N. Y., A CORPORA- TION OF NEW YORK.

' TELEPHONE-EXC HANGE SYSTEM. 1

Application filed Kay 7,1917. Serial No. 168,889.

T 0 all 'whomiit may concern:

Be it known that we, AMos F. DIXON and FRANK N. REEvEs, citizens of the United States, both residing 'at Newark, 1n the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Telephone-Exchange Systems, of which the following 1s a full, clear, concise, and exact description.

This invention relates to a telephone exchange system in which a call originating at one operators position may be extended over asuitable connecting circuit or trunk to a second operators position, and in which means are provided at such second operators position responsive to the operation of a manually controlled device at such first operators position to exhibit the number of the desired line at such secondopera'tors pos1- tion.

-It is an object of the present invention to provide an arrangement of this character which is adapted to be employed in connection with telephone exchange systems of the semi-automatic type in which the exhibiting device may be actuated in response to the operation of a registering-and controlling equipment which may be manipulated by an operator in the same manner as the ordinary equipment utilized in control-' ling semi-automatic switching apparatus. The operator sets up the number on a suitable key board in the same manner in which a numberis set up on the keyset of the ordinary registering and controlling equipment,:and as will more clearly appear, when thus set, may controlthe operation of automatic switches to extend a.connect1ng circuit to a trunk circuit leading to a manual op'erators position, and also may control means for exhibiting the desired number at such manual operators position.

In accordance with a feature of this invention, a printing device is'provided at a man- 45 ual operators position which is adapted to automatically operate in response to the operation of a registering and controlling equipment at another operators position to print the/number of the deslred line as determined by the operation of the manually operable device.

In accordance with a further feature of the invention. there is provided a printing device at an operators position, together witlr means for automatically.- associating such printlng device with a trunk line or Patented May 25,1920.

connecting circuit upon which the call is j awaiting attention, and such printing device is adapted to print a character indicating the particular trunk with which the printer has been automatically associated.

In accordance'with another feature of the 1I 1V6 I1t10 l'1,l3he indicating or recording deyice which, as far as certain features of the invention are concerned, may either be a printer, which is the preferred device, or any form of visual indicator, is adapted to be controlled by means of code impulses, the

preferred arrangement being a code form.

of various combinations of five positive or negative current impulses. These impulses are produced by means of registers which form a part of a registering and controlling equipment of known type, and which are adapted to be set in various positions in response to the'operation of certain number keys. These registers are set in response to the operation of the keys in identically the same manner as when the registers are to be utilized in controlling the operation of automatic switches, but in accordance with this feature of the inventiom'such registers are arranged so that after the registering and controlling equipment has been associated with the indicating or printing device, each register is successively and automatically driven through a plurality of additional positions, andfinfmoving through such additional positions, places upon a controlling circuit extending between the registering and controlling equipment and the indicator the particular combination of impulses necessary to cause the'indication or printing of the number or character represented by the set position of the registers.

In accordance with another feature of the invention, the printeror indicator, as the case may be, is arranged so that when the number has been printed or indicated, a suitable signal controlled from such printer or indicator is displayed before an operator 'to inform such operator that the call innot disconnected the particular trunk when such particular trunk has been previously used in establishing another connection.

In accordance with another feature of the invention, means are provided in case the initial digit of the number which it is desired to indicate or record is 0, to auto-' matically eliminate the corresponding recording or indicating operations.

In accordance with another feature of the invention, means are rovided whereby,.in case the number wliic cord or indicate is large, more thanone digit may be automatically recorded and indicated without the necessity of an additional recording or indicating'operation.

In the accompanying drawings, Figures land 2 represent dia ammatically an A operators connecting circuit and associated apparatus; Figs. 3, 4, 5 and 6 represent diagrammatically a registering and controlling equipment and associated apparatus; Fig. 7 represents diagrammatically a recording device adapted .to be associated with a connectin circuit at a B 'operators position; and ig. 8 represents one of such B operators connecting circuits. v

The complete system is shown with F g. 2 beneath-Fig. 1, Fig. 3 beneath Fig. 2, Fig. 4 beneath Fig. 3, Fig. 5 to the right of Fig. 3. Fig. 6 to the right of Fig. 4 and beneath Fig. 5, Fig. 8 to the right of Fig. 2 and Fig 7 above Fig. 8.

In the system disclosed, there is shown in Fig. 2, a connecting circuit of an A oper ators position, terminating in a plug When a call is initiated at such position, it

is 0111 necessary for the A operator to insert t e plug in the jack of calling line in order that her telephone may be automati-.

cally connected to a particularbonnecting circuit by means of the automatic listening key, and associated apparatus shown in Fig. 1. When the operator has ascertained the number of the desired line, she has only to set up this number on the keys of the registering and controlling equipment indicated in Figs. 5 and 6 in order to automatically control the extension of the particular connecting circuitto a trunk leading to a manual operators position in another exchange or at the same exchange shown in Fig. 8, and to also cause the printer disclosed in Fig. 7 to print the number of the desired line; and also the number of the particular trunk shown in Fig. 8. The registering and controlling equipment shown in Figs. 4, 5 and 6 is automatically associated with the connecting circuit by. means of the cord finders shown in Fig. 3, one of which is allotted for use with the next incoming call by means of the allotter also shown in Fig.

3. The selector switch which is utilized to extend the connecting circuit to the printer is of the type which isdisclosed in United it is desired to re-v States Patent No. 1,168,319 issued January 18, 1916, to Alben E. Lundell. The cord finder and allotter are also of similar construction to the cord finder and allotter shown in such patent. The registers shown in Figs. 5 and 6, forming a part of the registering and controlling equipment, are of the same mechanical construction as the re isters disclosed in United States Patent 0.

type disclosed inv United States Patent No.

. 1,127,808 issued February 9, 1915, to John N. Reynolds and Charles F. Baldwin, and the contacts operated b said sequence switches are in every-case esignated-by reference numerals having the same initial digit as the reference character utilized to designate the power'magnet of the corresponding sequence switch.

In referring to these sequence switch contacts in the specification, in order to avoid needless repetition, they will be referred to merely by the word contact followed by the reference character which is employed to designate them, and in parenthesis by the word position and a numeral indicating the particular position in which the sequence switch is located at the time.

Referring now to Fig. 7, the switch indi cated by the numeral 700, which is adapted to hunt for a trunk upon which a call has been extended and to connect a printer in be of any well-known type and is indicated as comprisinga shaft 714, carrying an arm 704, which is adapted to be moved over terminals leading to trunks as long as the I clutch magnet indicated at 701 is energized. This switch, however, carries upon the shaft a type wheel indicated at 715, which type wheel isprovided with a character corresponding to each of the trunks, which character is adapted to be brought opposite the printing hammer 717 of the printing magnet 711 when the brushes carried by the arm 704 have been stopped on the terminals of the trunk. A suitable mechanism, not shown, is provided for presenting a strip of paper or other recording medium between the type wheel and the hammer 717. The distributing switch, shown in the dotted rectangle in Fig. 7, is of the type disclosed in United States Patent No. 1,215,917, issued February 13, 1917, to O. A. Danielson and the printer, which is diagrammatically shown also in Fig. 7, is disclosed in United States Patent No. 1,201,809 issued October 17, 1916,.to Amos F. Dixon, to which reference may be had for the details of construction. Although the apparatus as outlined above is the type of apparatus which it is ,-preferred to use to carry out the invention,

itis obvious that e uivalent apparatus ci iuld be substituted Wit out departing from the s irit'of the invention, and as far as certain features of the invention are concerned any t pe, of apparatus adapted to be operatedto' isplay or indicate in any man- 1 ner the designation of the call may be em- Five digit numbers may plo ed.

rinters of the type disclosed in the abovementioned'patents are ad'a ted to operate in. response to different com mations of five sitive ornegative current impulses..

, pear hereinafter, and, as will be apparent from the specimen code given below, the maximum number of characters required in the system disclosed being seventeen.

Number or Impulse character.

combination.

It is obvious that any of the above characters could be replaced by letters or arbitrary sings on the type wheel if desired.

As soon asthe operator observes the calling lamp and inserts the plug 203 into the answering jack of the calling line a circuit is established for relay 201, which circuit extends from battery on the sleeve of the jack through sleeve of the plug 203, conductor 20 1, contact 101 (position 1), relay 201 to ground. Relay 201 closes at its left armature and front contact a circuit for the listening key sequence switch 100 which circuit extends from battery through motor magnet of the listening key sequence switch 100, contact 102 (position 1), conductor 103, front contact of. the relay 201 to ground,

whereupon the sequenceswitch 100 moves intoposition 7. 1

In osition 7 of the listening key sequence switc the operators telephone set is connected in operative circuit relation with the callin line, which circuit may be traced from th tip side of the calling line through the tip of he jack 203, conductor 205, contact 104 (position 7 conductor. 105, conductor 106,

' the operators telephone (not shown) and from thence by conductor 107 conductor 108, contact 109-.(position 7), conductor 206 to the ring side of the calling line. Battery for conversational purposes is placed upon this circuit from the ungrounded side of the battery through the winding 207 of the repeating coil, conductor 208, contact 110 (position 7), conductor 111 and then by conductor 107 to the telephone set of the operator,

and by conductor 108 to the telephone of the calling subscriber, and then back from the operator and the subscriber by conductors.l06 and 105, respectively, to the conductor 112, contact 113 (position 7), conductor 209 to the winding 210 of the repeating coil to the grounded side of the battery. Thus the operator is enabled to converse with the calling subscriber and ascertain the number desired.

In position 7 of the sequence switch 100 a circuit is established to drive the district sequence' switch 200 into position 2, which circuit extends from battery to the motor magnet of sequence switch-200, conductor 211, conductor 212, contact 101" (position 7 -conductor 2133, contact 214 (position 1) to ground. With the district sequence switch 200 in position 2 a circuit is established for the relay 301, which extends from battery to the relay 301, contact,304 in position 1,

. conductor 2155, contact 114; (position 7 conductor 216, contact 214 in position 2 to ground. -The relay 301 closes at its righthand armature and contact a circuit to drive the cord finder sequence switch 300 into position 2, which circuit extends from battery to the motor magnet of the sequence switch 300, contact 305 (position 1), front contact and right-hand armature of the relay 301 to ground. At the right of Fig. 3 within the dotted rectangle an allotter of the type disclosed in United States Patent 1,168,319 issued January 18, 1916, to Alben E. Lundell is diagrammatically shown. This allotter serves to allot a cord finder switch for use with the next incoming call by causing the cord finder sequenceswitch of the cord finder allotted to move from position 18 to position 1. As the allotter forms no part of the present invention it will not be further-described and it will be assumed that the cord finder shown in Fig. 3 has been allotted and that the corresponding sequence switch 300 has been moved to position 1 previous to the initiation of the particular call the progress of which is being traced. lVhen the sequence switch 300 reaches osition 2 a circuit'is closed for the uprive magnet 302 of the cord finder, which circuit extends from battery through up-drive magnet 302, contact 306 (position 2), front contact and right-hand armature of the relay 301 to ground. The original energizing circuit for the relay 301 is interrupted as the sequence switch moves out of position 1%. Such relay is maintained energized over either of two substitute circuits, one of whichextends from battery, relay 301, front contact and left armature thereof to the commutator C and by way of the interrupter brush 307 to ground, whlle such interrupter brush is asslng oversegments of the commutator 8 of the cord finder, and the other ofwhich extends frombattery to the relay 301, contact 304 (position 2) to the back contact and right-handv armature of the relay 303 to ground. Therefore, while the test brush 308 of the cord finder passes over terminals of cords which have not been taken for use, the relay 301 will be maintained energized. As soon as the particular cord which has been taken for use is encountered, a circuit is established from test relay 303, which circuit extends from battery to the relay 303, contact 309 (position 2), test brush 308, conductor 217, contact 114 (position 7), conductor 216, contact 214 (position 2) to ground.

It will be observed that the ground which makes the connecting circuit in Fig. 2 selectable in the cord finder extends by way of a contact of the district switch 200 and by a contact of the listening sequence switch 100.

The relay 303, when energized, opens at its right-hand armature and back contact 'one of the energizing circuits of relay 301,

and when the other energizing circuit for the relay 301 is opened at the commutator C when the cord finder brushes are centered upon the selected terminals, the relay 301 deenergizes, opening the circuit previously traced for the'up-drive magnet 302, and thereby stopping the upward movement of the cord finder. The deenergization of'relay 301 also closes a circuit to drive the cord finder sequence switch to position 3, which circuit extends-from battery to the motor magnet of the sequence switch 300, contact a 305 (position 2), back contact and right armature of the relay 301 to ground. The relay 303 is held up and thus prevents the reenergization of the relay 301 until the sequence switch 300 has reached position 3 by a circuit which extends from battery through relay 303, contact 309 in positions 2 to 2%, front contact and right-hand armature of relay 303 to ground. The relay 303 is also held up when the sequence switch 300 reaches position 3 by a circuit which extends from battery to the contact 309 in position 3, lefthand armature and front contact of relay 303, brush 310, conductor 218, contact 219 in position 2, to the back contact and left-hand armature of the relay 202 to ground.

In the meanwhile the o erator has set up the number of the desired line on her keyboard, which will be assumed was North 11-5-4-9-J. It will also be assumed that the North oflice is a manual oflice. As will more clearly a pear in response to the depression of the o ce key 501 of Fig. 5, which is assumed to be the North oflice key, the oflice selector will select a trunk leading to a B operators position at such' North ofiice, and the depression of the keys representing No. 11-5-4-9-J shown in Fig. 6 will cause the operation of the printing device shown in Fig. 7 associated with the B operators position for the purpose of printing the required number at such B operators position. For convenience and in order to prevent undue complication in the drawings, only one office key and one thousands, hundreds, tens and 504, contact of the key 501, relay 505 to ground. The operation of relay 3 is of no consequence at the present stage of circuit connections, and its function in a subsequent connection will be hereinafter described. The operation of the relays 504 and 505 placed ground upon the contacts 506 and 507 of the district registers, respectively, and the relay 503 closes the energizing circuits for the motor magnets 508 and 509 of such registers. These circuits may be traced from battery, contact 312 (position 3), and by conductors 510 and 511 in parallel, the magnets 508- and 509, back contacts of cut-ofi' relays 512 and 513, conductor-514, armature and contact of relay 503 to ground.

Therefore, as soon as the cord finder sequence switch reaches position 2, the district (position 1), relay '3, allotter contact 4 (position 1), conductors 514 and 515 in parallel and through the cut-01f relays 512 and 513 to the register contacts 506 and 507 which are closed when the registers reach position 16, to the armatures and contacts of energized relays 504 and 505 to ground.

The relays 512 and 513 when energized open the previously traced energizing circuits for the register power magnets 508 and 509, causing both registers to stop in the case assumed in position 16. Relays 512 and 513 also close a circuit to drive the cord finder sequence switch 300 into position 4, which, circuit extends to battery through the motor magnet of the sequence switch 300, contact 313 (position 3), conductor 516, left armature and contact of relay 512, front contact and armature of the relay 513, conductor 514, contact and armature of the relay 503 to ground. When the sequence switch 300 reaches position 4, a circuit is established to drive the sender sequence switch 400 into position 2, which circuit extends from battery through motor magnet of the sequence switch 400, contact 401 (position 1), conductor 402,-contact 314 (position 4),-

to ground. As in the case assumed, it is only necessary to employ a single selector switch to select a trunk leading to the manual office. The sequence switch 300 is arranged to move directl into position 5 without stopping at posltion 4, the circuit for driving sequence switch 300 into position 5 extending from battery through motor magnet of the sequence switch 300, contact 313 (position-4), to ground. However, with the sequence switch 300 in either position 4 or position 5 and the sequence switch 400 in position 2 and sequence switch 200 in position 2, the fundamental circuit is established for the purpose of controlling brush selection in the selector switch shown in Fig. 2. It will be remembered that the registers shown in Fig. 5 have been set in position 16, and, as indicated in the lower part of Fig. 5, the register contact 517 has closed a circuit leading to the No. 1 counting relay shown in Fig. 4, and the register contact 518 has closed a circuit to the No. 7 counting relay. These counting relays are of the well-known type such as is disclosed in the l nited States Patent No. 1,168,319 issued January 18, 1916, to Alben E. Lundell and operated in the same manner as in such patent so that when the No. 1 counting relay is energized, the counting relays will con trol the production of two impulses in the fundamental circuit, and when the No. 7 counting relay is energized such counting relays will control'the production of eight impulses in the fundamental circuit.

The fundamental circuit which is established at this time may be traced from battery through line relay 220, contact 221 (position 2) conductor 222, terminal 315, brush 316, conductor 317, contact 318 (position 4),

conductor 319, contact 403 (position 2), conductor 404, stepping relay 405, back contact and armature of the number 0' counting relay, conductor 406, front contact and right-hand armature of the relay 303 to ground. The relays 405 and 220 are energized in this circuit. The energization of the relay 220 establishes a circuit to drive the sequence switch 200 into position 3,

which circuit extends through the motor ister contact 517, conductor 519, contact 407 (position 2), conductor 408, armature and contact of the stepping relay 405 to ground. The relay 220, when the sequence switch 200 reaches position 3, closes a circuit for the up-drive magnet 224 of the, selector switch, which circuit may be traced from battery, magnet 224, contact 225 (position 3), f ont contact and left armature of the relay 220 back contact of the right armature of relay 202 to ground. As the interrupter brush 295 passes over the segments of the A com mutator of the selector due to the upward movement of the elevator rod 226, a shunt circuit for relay 405 is closed, which shunt circuit extends from battery through relay 220, contact and right armature of relay 220, contact 227 (position 3), contact 228 (position 3), to the A commutator of the selector switch, brush 295, contact 229 (position 3) to ground. As the No. 0' counting relay is energized after two such shuntings of the stepping relay 405, the fundamental circuit is opened by the energization of the No. 0 counting relay. The opening of the fundamental circuit causes the release of the line relay 220 when the brushes of the selector are properly centered, and, consequently, the opening of the previously traced circuit for the up-drive magnet 224. The release of the line relay 220 also establishes a circuit to drive the sequence switch 200 into position 4, which circuit extends from battery, through the'motor magnet of sequence switch 200, through contact 230 (position 3), back contact and left armature of relay 220, back contact and right armature of relay 202 to ground.

In position 4 of the sequence switch 200 a circuit is established for the trip magnet 231, which circuit extends from battery, through the trip ma not contact 232 (position 4) to ground. s the trip magnet has been thus energized after two-shuntings of the stepping relay, when the elevator rod is again set in motion, as will be hereinafter described, the second set of brushes of the selector switch will be tripped, and it will th elevator rod is the set tripped. When .the No. 0' counting relay opened the fundamental circuit as above described, it also closed at its front contact a circuit to drive the sender sequence switch 400 out of posi- .tion 2 and into position 4. This circuit extends from battery, through the motor magnet of sequence switch 400, contact 408 (position 2), front contact and armatureof the 0 counting relay, conductor 406 to and opens the counting relay set 7 and 7", although not shown, should readily be understood. After the stepping relay 405 has been energized and cleenergized eight times, No. 0 counting relay is ener ized in the usual manner undamental circuit. The opening of the fundamental circuit causes the relay 220 to release when the brushes are centered on the terminals, and hence the shunt circuit by way of the commutator B is open, and such relay when released closes a circuit todrive the sequence switch 200 into position 6,. which circuit extends ground at the right armature and front mm \from battery, through the motor magnet of .tact of relay 303. With the sender sequence switch 400 in position 4 and the cord finder sequence switch 300 in position 4, and the sequence switch 200 in position 4, the fundamentalcircuit is again established whichnow extends from battery, line relay 220, contact 221 (position 4), conductor 222,

terminal 315, brush 316, conductor'317 contact 318 (position 4), contact 403 (position 4), conductor 404, stepping relay 405, armature and back contact of the 0' counting relay, conductor 406, front-contact and right armature of the relay 303 to ground. The energization of the relay 220 at, this time drives the sequence switch-200 into position 5 over'a circuit which .extends rom battery, motor magnet of sequence switch 200, contact 225 (position 4), front contact and left-hand armature of relay 220, back contact and right armature of relay 202 to ground. With the sequence switch 200 in" position 5, acircuit is again closed for the up-drive magnet 224, which extends from. battery through the magnet 224, contact 225 (position 5), front contact and left-hand armature of the relay220, back contact and right armature of relay 202 to ground. s the elevator shaft 226 moves upward the set of brushes are tripped, and when the brush 233 makes contact-with the segments of the commutator B, a shunt circuit is established which intermittently shunts the stepping relay 405. This shunt circuit extends from battery, through relay 220, front contact and right-hand armature thereof, contact 227 (position 5), contact 228 (position 5), commutator B, brush 233 to ground at contact 229 (positi0n5).

Upon the first energization of relay 405 a circuit is established for the No. 7 count ing relay, which circuit extends from battery, through the No. 7 counting relay, back contact of the No. 7 counting relay to the re ister contact 518, conductor 520, contact 40% (position 4), conductor 408, armature and back contact of stepping relay 405 to ground. The counting relay sets 5 and 5' to 8 and 8' inclusive have been omitted from the drawing to avoid needless duplication, and as the function of all sets of counting relays is identical, the above current through front contact, a circuit to drive the sequence switch 400- into position 5, which circuit magnet of the sequence switch 400, contact 408 (position 4), front contact and armature of the 0' counting relay, conductor 406, front contact and right-hand armature of relay 303 to ground. I

As the sequence switch 200 reaches position 6, a circuit is. established for the test relay 234. This circuit extends from battery, through the upper winding of the test relay 234 contact 235 (position 6), to ground. litelay 234 when energized closes a circuit to drive the sequence switch 200 into position 7 which circuit extends from battery, through the sequence-switch 200, contact 225 (position 6), front contact and upper armature of relay 234, back contact and right armature of relay 202 to ground. When the sequence switch 200 reaches position 7, a circuit is established for the up drive magnet 224, which circuit extends from battery, through the ma'gnet224, contact 225 (position 7), front contact and upper armature of relay 234 to ground at the back contact and right-hand armature of the relay 202. The brushes are thereextends from battery, through the motor V upon moved over the'group of terminals selected for the purpose of hunting for an all district selectors in which it appears will be without potential. If, however, the trunk individual to. the terminal 236 is occupied,

having been seized by another district selector, a ground will be placed upon such terminal by way of the test brush 237, conductor 238,, back contact and lower armature of test relay 234, contact 219 (position 6% to 16%), back contact of relay 202 of the district selector in connection with the trunk of the particular time, to ground. Therefore, in

any given case, as long as the test brush 237 of the district selector passes over terminals 236 individual to trunks which have been seized by other district selectors, there will be a ground upon such test terminals and the relay 234 will be maintained energized over a circuit which extends from battery, through the lower winding of relay 234,

front contact and armature thereof, conduc-' tor 238, test brush 237, test terminal 236 to ground. In order to maintain the relay 234 energized while. the brush 237 is passing between terminals, a substitute energizing circuit is maintained for said relay over a circuit which extends from battery, through the upper winding of relay 234, contact 235 (position 7), the C commutator, brush 239,

contact 225 (position 7) front contact and upper armature of relay 234 to the back con-. tact and right-hand armature of relay 202 to ground. When the test brush 237 reaches a terminal 236 which is individual to an idle trunk, which it will be assumed is the trunk shown in Fig. 8, as soon as the brushes are centered upon the terminals thereof, both energizing circuits previously traced for the. relay 234 will be opened, causing the relay 234 to release. Relay 234 when released opens the circuit of the up-drive magnet 224 and hence stops the selector with the brushes on the terminal of an idle trunk. The relay 234 when released also closes a circuit to drive the sequence switch 200 into position i terminal 323, conductor 240, contact 232 (position 8), to ground. The intermediate positions from 5 to 9 of the sender sequence switch 400 are utilized'bnly in case it is desired to bring about other selections than those necessary in the system illustrated. For example, if the selector switch shown in Fig. 2 selected a trunkleading to a second selector switch and such second selector switch was utilized to select a trunk leading (position 8 contact 227 (position 8), conductor 241, terminal 324, brush 325, conductor 326, contact 410 (positions 6 to 8) to ground. -The line relay 220 when energized closes a circuit to drive the sequence switch 200 to position 11. This circuit extends from battery through the motor magnet of-the sequence switch 200, contact 225' (position8), front contact and left-hand arma ture of the relay 220, right-hand armature and back contact of relay 202, to ground.

While the various selecting operations above described have been taking place for the purpose of associating the connecting .circuit with a trunk leading to the manual ofiice, the number registers, shown in Fig. 6, may be moved to their set position'as determined by the particular keys depressed. These registers are of the t vpe employed in the United States Patent K 0. 1,168,319 issued January 18, 1916, to Alben EQLundell, but as will more clearly appear hereinafter such registers are arranged to o )erate in a different manner, and for a di erent pur-.

pose. As the re isters are for the. purpose of controllin the production of code impulses for the operationof the printing device, such code being formed of combinations of five positive and negative current impulses, the registers are not limited to ten I setting positions,because'it is possible to obtain several more than ten different code combinations with five impulses, and, therefore, the type wheel of the printer, instead of having merely numbers from zero to nine, may be provided with numbers from ten to fifteen oreven twenty-five. By suitably arranging the register, it is possible to print a five digit number in response to four sets of code impulses, or what amount to the same thing, by the employment of four registers, as two digits may be printed in response to a single set of impulses.

In the system disclosed, for example, it will be assumed that it'is desired to print numbers up to twelve thousand. Therefore, the thousands register is adapted to be con trolled by two sets of keys, there being one set of keys from zero to nine which are operated when it is desirer to register zero to nine, and a separate key which is depressed only in case the number which it is desired to register is more than nine thousand; One of the thousands keys is indicated in Fig. (5 by the reference character 600, this being, as shown, the number one thousand key. The ten thousands key is indicated at 601. Therefore, in order to set the register in the position to register eleven thousands, or in other words the eleventh position, the key 601 is first depressed and then a keyGOO. it being apparent from an inspection of the keys associated with the thousands register,

in case the key 600 is depressed without the the key 600 and battery. lVhereasflf the kev (301 is depressed, the energizing circuit of the register cut-ofi' relay 602 will be by way of the register spring 604. The station register is also arranged somewhat differently from the registers shown in the prior art, there bemg utilized fourteen positions although there are only -five stations. The contacts and keys are arranged so that w th the key marked direct depressed a station register will stop in either position zero or nine, the key' marked J in position 1 or 10, the key marked M in position 2 or 11, the key marked R in position 3 or 12, and the key marked 1V in position 4 or 13. The arrangement is utilized because the registers have no normal position, and as will herelnafter appear, it is necessary for the register to move in all cases through five positions beyond its setting position. Therefore, in order to limit the extent of the travel of the register in response to the depression of the next key, two positions are provided on the register individual to each key, which positions are spaced apart nine positions, WlllCll is the maximum number of positions utilized in setting and.controllingmovement of the station register in response to the depression of any key. In the particular instance which is about to be described, it has been assumed that the ten thousands key 601 has been depressed, the number one thousands key indicated at 600 has been depressed, the number five hundreds key indicated at 605,

the number four tens key indicated at 606,

the number 9 units key indicated at 607 and the number J station key indicated at 608. Each of the keys of the station register,

which are the last keys depressed in setting" up a number, operates, when depressed, a contact indicated at 609. This contact closes a circuit for the start relay 610, provided the cord finder is in position 1. to 5. This circuit extends from battery (Fig. 3), contact 311 on the cord finder (positions 1 to 5), allotter contact 1 (position 1), allotter contact 2 (position 1), allotter relay 3, allotter contact 5 (position 1), conductor 521, start relay 610, to the contact 609 to ground.

Relay 610 when energized established circuits for the power drive magnets 622, 623, 624, 625 and 626 of the thousands, hundreds, tens, units and station registers, respectivel These circuits extend from battery (Fig. 3 by way of contacts 312 and 327 (positions 2 to 6), and thence in parallel over conductors 411, 412, 413, 414 and 415 to the motor magnets 622, 623, 624, 625 and 626 to inner armature and back contacts of relays 602, 630, 631, 632 and 633, to conductor 611, front contact and inner armature of relay 610 to ground. When the thousands register reaches position 11, thehundreds register reaches position 5, the tens registerreaches position 9 and the station register reaches position 1 or 10, circuits for the register cutofi' relays 602, 630, 631, 632 and 633 are established as follows: from battery, contact spring 311 (position 5), allotter contact 1 (position 1), allotter contact 2 (position 1), relay 3, allotter contacts 5 and 6 (position 1) and thence in paralled by conductors 522, 523, 524, 525 and 526 to register cut-ofi' relays 633, 632, 631, 630 and 602, respectively,

;gets are opened and the thousands register 1s stopped in position 11, the hundreds register in position 5, the tens register in position 4, the units register in position 9-and the station register in position 1 or 10. The

register cut-ofl? relays when energized also close a series circuit to drive the cord finder sequence switch 300'into position 6, which circuit extends from battery through the motor magnet of sequence switch 300, contact 313 (position 5), conductor 527, outer armatures and front contacts of the relays 602, 630, 631, 632 and 633, inner armature and contact of the relay 610 to ground.

In position 6 ofthe sequence switch 300, a circuit is closed for the released magnets, which when operated release all of the de-. pressed keys of all of the registers, there being four of these release magnets diagrammatically'shown in Fig. 5 and indicated at 528. The energizing circuits for these release magnets extend from battery through the contact 328 (positions 6 to 6%),

528 to ground. If all of the keys are restored by the operation of the release magnets, the relay 3, which was energized in all of the circuits traced through the keys, will be denergized, driving the sequence switch 300 into position 7 over a circuit which extends from battery to the motor magnet of the sequence switch 300, contact 305 (position 6), back contact and right-hand armature of the relay 3 to ground.

When the sequence switch 300 reaches position 7 a circuit is closed for the allotter power magnet 10, which extends from battery to the magnet 10, contact 329 (position 7), allotter contact 8 (position 1), to ground. The allotter thereupon operates in the usual manner to allot another cord finlrller for use in connection with the next ca As the sender sequence switch 400 reached position 9, as above described, while the number registers were being set, the cord finder sequence switch 300 is advanced to position 8 by a circuit which extends from battery through the motor magnet of the sequence switch 300, contact 331 (position 7), conductor 332, contact 410 (position 9), to ground. With the sequence switch 200 in position 11, sequence switch 300 in osition 8, and sequence switch 400 in position 9, a circuit is established for the relay 800 associated with the trunk which has been, selected for use, which circuit extends from battery, through the left-hand .winding of relay 412 contact 436 (position 9), conductor 437, contact 318 (position 8), conductor 317, brush 316, terminal 315, conductor 222, contact 221 (position 11), contact 227 (position 11), brush 243, terminal 242, trunk conductor 801, upper armature and back contact of relay 805, relay 800, to the back contact and armature of the relay 802 to ground. The relay 412 closes at its outer armature and front contact a circuit to drive the sequence switch 300 into position 9, which circuit extends from battery through motor magnet of the sequence switch 300, contact 333 (position 8), conductor 334, front contact and outer armature of the relay 412 to ground. The energization of the relay 800 closes a circuit to start the switch indicated at 700 to hunt for the trunk which has been taken for use and to connect thereto the printer shown diagrammatically in Fig. 7. The circuit established by the energization of relay- 800 for the clutch magnet of the sequence switch 701 extends from battery through the outermost armature and back contact of the test relay 702, clutch magnet 701, conductor 703, front contact and inner armature of the relay 800 to ground. As soon as the clutch magnet 701 is energized, the arm 704 is moved by mechanism (not shown) to cause the brushes 705, 706 and 707 to pass over terminals individual to a plurality of trunks with which the printer may be used. As soon as a set of contacts 708, 709 and 710, individual to the trunk shown in Fig. 8, which has been taken for use, is reached, a circuit is established from battery, left-hand winding of test relay 702, printer magnet 711, brush 705, contact 708,

conductor 712, the outer armature and con-' tact of the relay 800 to ground. The relay 702 when energized closes at its inner armature a locking circuit for itself, which circuit extends from battery, printer contact 7 36, conductor 737, inner armature and contact of relay 702, right-hand winding of relay 702 to ground.

Relay 702, when energized, opens at its outermost armature the energizmg circuit for the clutch magnet 701 and stops the switch with the brushes 705, 706 and 707 in position to make contact with the desired trunk. The magnet 711 is also energized at this time for the purpose of recording --,the number of the trunk with which the printer has been associated. As shown in Fig. 7 of the drawing the shaft 714, which carries I the arm 704, also carries a type wheel 715. A strip of paper indicated at 716 is adapted to be presented by any suitable mechanism between the type wheel 715 and the plunger 717. The type wheel carries suitable charaoters or numbers which are spaced about the plunger and the type wheel in the same relation as the trunks are connected to the stationary contacts of the switch, so that tends from battery through the normal con-' tact of relay 803, relay 802, conductor 718, terminal 710, brush 707, to ground at the middle armature of the relay 7 02. The relay 802 closes also a circuit for relay 805, from battery, normal contact of relay 803,

relay 802, left-hand armature and contact.

thereof, upper winding of relay 805 to ground. The relay 805 does not operate as it is sho'rt-circuited by the ground at the armature of relay 7 02. The energization of the relay 802 opens the circuit previously traced for the relays 800 and 412, both of which are deenergized. Relay 412, when deenergized, closes a circuit to drive the sequence switch 300 to position 10, which aircuit extends from battery through the motor magnet, sequence switch 300, contact 330 (position 9), conductor 337, back contact and armature of relay 412 to ground.

With the sequence switch 300 in position 10, and sequence switch 400 in position 9, relay 412 and relay 405 are energized over a circuit extending from battery, through the left-hand winding of relay 412, contact 436 (position 9), conductor 437, contact 318 (position 10), contact 403 (position 9), conductor 404, stepping relay 405, back contact of the No. 0 counting relay, conductor406, contact and right-hand armature of relay 303, to ground. The energization of the relay 412 at this time closes a circuit to drive the sequence switch 400 in position 10, which circuit extends from battery, through the motor magnet of sequence switch 400, contact 401 (position 9), conductor 335, contact 333 (position 10), conductor 334 to front contact and outermost armature of relay 412 and ground. With the sequence switch 400 in position 10, a circuit is closed for the power magnet 622 of the thousands register, which circuit extends from battery, contact 613 (position 1), conductor 416, contact 417 (position 10), conductor 411, power magnet .622 of the thousands register, back contact and innermost armature of the register cut ofi? relay 602, conductor .418, contact 419 .(position 10), conductor 335, contact 333 (position 10), conductor 334, the front contact and outermost armature of the relay 412 to ground. As the thosuands register rotates, the contact 614 is closed between each position, thus connecting ground to the energizing circuit-of the relay 412 and relay 405 at a point between such relays, thereby shunting the .ste ping relay This shunt circuit exten s from the relays, which energizing circuit extends from battery through the N0. 4 countin relay, armature and back contact of the o. 4

; counting relay, contact 420, conductor 408 to the armature and contact of relay 405, so that for the first energization of the relay 405, the No. 4' relay will be energized, and after the fifth operation of the stepping relay 405, the No. 0 counting relay will be energized. Thus, the register 622 will have taken five steps when the; No. 0 counting relay is ener ized and opens the energizing circuits for t e relay 412 and the relay 405, thus stopping the register. :Before considering. the efi'ect of opening the circuit for'the relay 412 at this time, the operation of the thousands .register in controlling the printer will be described. With the sequence switch 200 in position 11, the sequence switch 300 in position 10, and the sequence switch 400 in position 10, the printer control circuit extending between the registers and the printers is established. This circuit extends from either positive or'negative battery, de-

' pending upon the particular register springs which are operated, thence by conductors 421, 422, 423 and 424 to the contact 425, or by way of the conductor 426 to contact 427 and from contacts 425 and 427 to conductor 428, the particular path from the negative and positive batteries to conductor 428 de pending upon the position at any given time of the register contact springs, and the sequenceswitch 400. From conductor 428, the printer control circuit extends to conductor 326, brush 325, terminal 324, conductor 241, contact 244 (position 11), conductor 245, brush 246, terminal 247, trunk conductor 804, back contact and lower armature of relay 805, conductor 719, terminal 709, brush 706, to either the positive or negative polarized relays indicated at 720 and 721. As it was assumed that the thouosi.

sands register was set'in position 11, positive batter is placed on the printer control circuit an as itpasses position 12, positive battery is placed thereon, which is followed by positive battery when the register reaches 13, and, also by positive battery when the register reaches 14, and finally negative batterywhen the thousands register reaches. position 15. Thus,-in positions 11 12, 13, 14 andil5, four positive impulses followed by a negative impulse are placed upon th'e'prin'ter control circuit so that the relay 720 will be energized four times and the rela 721 once. By reference to the code given a ove, it will be seen that this combination of impulses will cause the printing of the numeral 11.

Upon the first ener ization of the relay a circuit which extends from battery through the armature of either of the relays 720 or 721, conductor 723, magnet 722 to ground. Due to the successive operations of the magnet 722, the set of contacts 725 to 729 are successively closed and opened, only one contact of the set being closed at any one time. This is in accordance with the Patent No. 1,215,917, issued February 13, 1917-, to Oscar A. Danielson, hereinbefore mentioned. Itis thought that it ,will be easilv understood that the next three energizations of the relay 720 will cause the energization. of the selecting magnets 731, 732 and 733. When in response to the last impulse, which is negative, the relay 721 is energized, no circuit is established to the selecting magnets but as the magnet 722 is energized, contact 724 is closed, and the relay 735 is energized overa circuit which extends from battery, left-hand armature and contact of the relay 7 21, conductor 723, contact 724, relay 735 and the armature and back contact of the clear-out relay 738.

As soon as the relay 735 is energized, which occurs only after all of the impulses have been sent to the printer and the selecting magnets have been energized, and the selecting disks (not shown) have been positioned, a circuit is established for the release magnets 739, which circuit extends from battery through magnets 739, inner armature and contact of the relay 735, winding of relay 735, back-contact and armature of the clear-out relay 738, to ground. The operation of the release magnet closes a circuit for the start magnet 740 and at the same time permits the selected lever to mature of the clear-out relay 738 to ground. The operation of the start magnet releases. the type shaft indicated at 742 and per-v mits the type wheel'toirotate until the selected lever 741 engages the stop arm 743 carried by the type holder.' As soon as the stop arm 743 engages with the selected-lever 741, the type wheel is in the proper position for prmtihg the selected character, in the case assumed to be'the character 11, which is accomplished by the operation of the printing hammer in response to the energi'zation of the magnet 745. The printing hammer is not shown nor is the paper carriage, as the specific construction of the printer forms no part of the present. invention. type wheel is properly positioned a circuit is established for the clear-out relay 738, the space operating relay 744 and the printing magnet 745. This circuit extends from battery and through the clear-out relay 738, right-hand winding of the space controlling relay 744, printing 'magnet 745, type wheel shaft 742, stop 743, selected lever 741 to ground. The magnet 745 operates to cause the impression of the character represented by the position of the type wheel and relay 744 closes a circuit from the space magnet 746, and a locking circuit for itself, as will be apparent from an inspection of the drawing. The clearout relay 738 opens the previously traced circuits of the selecting magnets and the various other magnets and relays and restores all of the printing apparatus to normal. As soon as the release magnet is restored the energizing circuit for the relays 744 and 738 is opened at the lever 741, permitting such relays to release. As soon as the space magnet operates, it opens the locking circuit of the relay 744 and at the same time moves the paper carriage through a Space in order to present a clean space on the paper for recording the next character. 7

It will be recalled that as soon as the fifth impulse was sent over the printer control circuit the thousands register was stopped, due to the energization of the No. 0 counting relay, which, in turn, opened the energizing circuit for the relays 412 and 405. The release of the relay 412 closes a circuit to drive the sequence switch 400into position 11, which circuit extends from battery through the motor magnet of sequence switch 400, contact 401 (position 10), conductor 336, contact 330 (position 10), conductor 337 to the back contact and outer As soon as the armature of the relay 412 to ground. As

. soon .as the sequence switch400 reachespjosition 11 the locking circuits of. the counting relays are opened at; the contact spring 490, and such relays are restored to inormal.'7o Therefore, in position 11 of the sequence switch 400 a circuit forthe relays 412 and 405. .18 again established, which circuit extends from battery through left-hand windmg of the relay 412,- contact'436 (position 11 conductor 437, contact 318 (position ,10),'.'co'ntact 403 (position 11 conductor 404, stepping-relay 405, back contact and armature ofthe' number 0' counting relay, conductor 406, front contact and ri ht arm'ature of the relay 303 to ground. he energizatlo'n of the relay 412 at this time establlshes a circuit to drive the sequence switch I 400 into position 12, which circuit extends from battery through the motor magnet of the sequence switch 400, contact 401 (position 11), conductor 335, contact 333 (position 10), conductor 334, front contact and 'outer armature of the relay 412 to'ground. 'Wlth the sender sequence switch 400 in po- ,90

sition 12 the printer control circuit is again established and extends from conductor 428 through contact'425 (position 12) by way of conductor 422 to the contact springs actuated by the hundreds register As soon as the stepping relay 405 is energized, the No. 4 counting relay will be energized, as in the previous case, and as soon as the relay- 412 is energlzed a circuit is closed for the power magnet 623 of. the hundreds register, which circuit extends from battery, contact 638 of the hundreds register, conductor 615, contact 417 (position 12), conductor 437, power magnet 623, back contact and inner armature of the cut-oil relay 630, conductor 418, contact 419 (position 12), conductor 335, contact 333 (position 10), conductor 334 to the front contact and outer armatureof relay 412. The hundreds register now moves through'five additional positions in the same manner as the thousands register moved through five positions under the control of the stepping magnet 405 and the counting relays, the stepping magnet being controlled by register spring 616 in the half or intermediate positions. As the hundreds register has been set in position 5, the first impulse placed upon a printer control circuit is negative, which is followed by negative inposition 6, negative in position 7 positive in position 8 and negative in position 9, which'is the'impulse combination necessary to select and cause the re-, cording of the character 5. Consequently, there will be three energizations of the relay 721 followed by'an energization of the relay 720 and by an energization of the relay 721. It is thought that it will be obvious from the description given of the operation of the printer in printing the character 11 that this combination will result in the ehergization of the selecting magnet 733 and the selection of the suitable selecting lever 741 to cause the printing of the character 5. After the hundreds register has ppssed through the five extra positions, the 0. 0' relay is energized. and the relays 412 and 405 are decnergized. The previously traced circuit for the power magnet 623 is opened when the relay 412 releases, and, furthermore, the release of the relay 412 closes a circuit to drive the sequence switch 400 into position 13, which circuit extends from battery to the motor magnet of sequence switch 400, contact 401 (position 12), conductor 336, contact 330 (position 10), conductor 337, back contact and outer armature of the relay 412 to ground.

As soon as the sequence switch 400 reaches position 13 the counting relays are restored to normal, and the energizing, circuit for the relays 412 and 405 is again established. This circuit is the same as that in which these relays have been previously energized and will not be-again traced. ,-However, as soon as the relay 412 is energized, a circuit is established to drive the sequence switch 400 into position 14, which circuit extends from battery to the motor magnet of the sequence switch 400, contact 401 (position 13), con

ductor 335. contact 333 (position 10), con-- ductor 334 to the front contact and outer armature of: the relay 412 to ground.

In position 14 of the sequence switch 400 a circuit is established for the motormagnet 624 of the tens register, which circuit extends from battery, contact 440 (position 14) conductor 413, motor magnet 624, armature and back contact of the relay 631, conductor 41S, contact 419 (position 14), conductor 335, contact 333 (position 10), conductor 334, armature and contact of the relay 412 to ground. A circuit is also established for the No. 4 counting relay by way of the contact 420 and the armature and contact of the stepping relay 405, and, as in the case of the thousands register, when the tens register has passed through five positions the relay 405 is shunted that number of times at the spring 617, the No. 0 counting relay is energized, opening the energizing circuits for the relays 412 and 405, and, con sequently, the energlzing circuit of the power magnet 624.

It will be observed as the tens register movesthrough positions 4, 5, 6, 7 and 8,

the following code of impulses are placed upon the conductor 423 by the tens register springs and, by way of the contact 425 in position 14, are impressed upon the printer control circuit: negative, negative, negative, negative. positive. This particular combi nation of impulses will cause the printer to operate as before described to print the character 4. When the relay 412 is deenergized, due to the operation of the No. 0' counting relay, a circuit is established to drive-the sequence switch 400 into position 15, which circuit extends from battery through motor magnet of the sequence switch 400, contact 401 (position 14), 0011-" magnet of the sequence switch 400, contact 401 (position 15), conductor 335, contact tact and outer armature of the relay 412 to ground. In osition 16 of the sequence switch 400 wit the relays 412 and 405 energ zed, the number 4 counting relay is energized, and a circuit is established for the motor magnet 625 of the units register,

which circuit extends from battery, contact 440 (position 16), conductor 414, ma net 625, back contact and inner armature o the relay 632, conductor 418, contact 419 (posipos1 tion 16), conductor 335, contact 333 333 (position 10), conductor 334, frontcom tion 10), conductor 334, front contact and outer armature of the relay 412 to ground.

The units register thereupon begins to rotate and continues to rotate until, due to five shuntings of the ste ping relay 405, the No. 0 relay is energize openin the circuit of the relays 412 and 405, an consequently,

the circuit of the power magnet 625. As it was assumed that the units register was set in position 9, the following series of inipulses is impressed upon the conductor 424 and through the units register springs by way of contact 425 (posltion 16) on the printer control circuit as the units register moves from position 9 to position 13: neg ative, positive, positive, positive, positive. These impulses passing over the printing control circuit operate the printer as before described to cause the selection and printing of the character 9. The release of the relay 412, in addition to opening the circuit of the power magnet of the units register, also drives the sequence switch400 into position 17 over a circuit which extends from battery through motor magnet of the sequence switch 400, contact 401 (position 16), conductor 336, contact 330 position 10 conductor 337, back contact and outer armature of the relay 412 to ground.

As the sequence switch 400 leaves position 12 the previously traced lockin g circuits for the counting relays are opened at the contact 490, and the circuit prevlously traced 

